Petra Kvitova, Elena Rybakina and Madison Keys all take to the court for their first round matches later
Daniil Medvedev is out of the US Open after a dramatic first round loss to Benjamin Bonzi.
The former champion lost out in five sets in a match marred by an incident when a photographer stepped onto the court.
Medvedev subsequently challenged the umpire before play continued.
Elsewhere in the men's draw, Novak Djokovic came through his encounter with Learner Tien in straight sets.
In the women's draw, Petra Kvitova, Elena Rybakina and Madison Keys all take to the court for their first round matches later.
Emma Radacanu and defending champion Aryna Sabalenka both came through their games yesterday unscathed.

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